Identification of DC–DC buck converter dynamics using relay feedback method with experimental validation

Identification of DC–DC buck converter dynamics using relay feedback method with experimental validation

For access to this article, please select a purchase option:

Buy article PDF
(plus tax if applicable)
Buy Knowledge Pack
10 articles for £75.00
(plus taxes if applicable)

IET members benefit from discounts to all IET publications and free access to E&T Magazine. If you are an IET member, log in to your account and the discounts will automatically be applied.

Learn more about IET membership 

Recommend Title Publication to library

You must fill out fields marked with: *

Librarian details
Your details
Why are you recommending this title?
Select reason:
IET Circuits, Devices & Systems — Recommend this title to your library

Thank you

Your recommendation has been sent to your librarian.

Accurate dynamics of power converters are necessary to achieve good control performance. In this study, the dynamical model of the DC–DC buck converter is identified by the relay feedback method. The relay is connected in the closed loop to produce a limit cycle output. The important information of the oscillatory output is used for the identification. The relay is approximated using dual-input describing function (DIDF) in the mathematical modelling. DIDF can handle symmetric and asymmetric limit cycle outputs. The converter is modelled as a second-order plus dead-time system. Using the gain and phase angle criteria, analytical expressions are derived to estimate the dynamics. The converter dynamics obtained from the proposed method are compared with that estimated using the state-space averaging method. The model is also identified from the real-time experiment. To check the efficacy of the identified model, a model validation test is performed.


    1. 1)
      • 1. Renaudineau, H., Martin, J.-P., Nahid-Mobarakeh, B., et al: ‘DC–DC converters dynamic modeling with state observer-based parameter estimation’, IEEE Trans. Power Electron., 2015, 30, (6), pp. 33563363.
    2. 2)
      • 2. Wang, J.M., Wu, S.T.: ‘Sensorless control scheme for synchronous buck converter’, IET Circuits Devices Syst., 2016, 10, (3), pp. 181191.
    3. 3)
      • 3. Babaei, E., Varesi, K., Vosoughi, N.: ‘Calculation of critical inductance in n-input buck dc–dc converter’, IET Power Electron., 2016, 9, (12), pp. 24342444.
    4. 4)
      • 4. Wang, J., Li, S., Yang, J., et al: ‘Finite-time disturbance observer based non-singular terminal sliding-mode control for pulse width modulation based DC–DC buck converters with mismatched load disturbances’, IET Power Electron., 2016, 9, (9), pp. 19952002.
    5. 5)
      • 5. Vlad, C., Rodriguez-Ayerbe, P., Godoy, E., et al: ‘Advanced control laws of DC–DC converters based on piecewise affine modelling. Application to a step-down converter’, IET Power Electron., 2014, 7, (6), pp. 14821498.
    6. 6)
      • 6. Sun, J., Yang, J., Zheng, W.X., et al: ‘GPIO-based robust control of nonlinear uncertain systems under time-varying disturbance with application to DC–DC converter’, IEEE Trans. Circuits Syst. II, Express Briefs, 2016, 63, (11), pp. 10741078.
    7. 7)
      • 7. Middlebrook, R., Cuk, S.: ‘A general unified approach to modelling switching-converter power stages’. Proc. IEEE Power Electronics Specialist Conf., Ohio, USA, 1976, pp. 1834.
    8. 8)
      • 8. Vargas, A.N., Sampaio, L.P., Acho, L., et al: ‘Optimal control of DC–DC buck converter via linear systems with inaccessible Markovian jumping modes’, IEEE Trans. Control Syst. Technol., 2016, 24, (5), pp. 18201827.
    9. 9)
      • 9. Xiao, W., Dunford, W.G., Palmer, P.R., et al: ‘Regulation of photovoltaic voltage’, IEEE Trans. Ind. Electron., 2007, 54, (3), pp. 13651374.
    10. 10)
      • 10. Maity, S., Suraj, Y.: ‘Analysis and modeling of an FFHC-controlled DC–DC buck converter suitable for wide range of operating conditions’, IEEE Trans. Power Electron., 2012, 27, (12), pp. 49144924.
    11. 11)
      • 11. Miao, B., Zane, R., Maksimovic, D.: ‘System identification of power converters with digital control through cross-correlation methods’, IEEE Trans. Power Electron., 2005, 20, (5), pp. 10931099.
    12. 12)
      • 12. Johansson, B., Lenells, M.: ‘Possibilities of obtaining small-signal models of DC-to-DC power converters by means of system identification’. Proc. IEEE Telecommunications Energy Conf., Arizona, USA, 2000, pp. 6575.
    13. 13)
      • 13. Åström, K.J., Hägglund, T.: ‘Automatic tuning of simple regulators with specifications on phase and amplitude margins’, Automatica, 1984, 20, (5), pp. 645651.
    14. 14)
      • 14. Majhi, S.: ‘Relay based identification of processes with time delay’, J. Process Control, 2007, 17, (2), pp. 93101.
    15. 15)
      • 15. Liu, T., Gao, F., Wang, Y.: ‘A systematic approach for on-line identification of second-order process model from relay feedback test’, AIChE J., 2008, 54, (6), pp. 15601578.
    16. 16)
      • 16. Panda, R.C., Vijayan, V., Sujatha, V., et al: ‘Parameter estimation of integrating and time delay processes using single relay feedback test’, ISA Trans., 2011, 50, (4), pp. 529537.
    17. 17)
      • 17. Bajarangbali, R., Majhi, S., Pandey, S.: ‘Identification of FOPDT and SOPDT process dynamics using closed loop test’, ISA Trans., 2014, 53, (4), pp. 12231231.
    18. 18)
      • 18. Liu, T., Wang, Q.G., Huang, H.P.: ‘A tutorial review on process identification from step or relay feedback test’, J. Process Control, 2013, 23, pp. 15971623.
    19. 19)
      • 19. Berner, J., Hägglund, T., Åström, K.J.: ‘Asymmetric relay autotuning-practical features for industrial use’, ISA Trans., 2016, 54, pp. 231245.
    20. 20)
      • 20. Shen, S.H., Wu, J.S., Yu, C.C.: ‘Autotune identification under load disturbance’, Ind. Eng. Chem. Res., 1996, 35, (5), pp. 16421651.
    21. 21)
      • 21. Panda, R.C.: ‘Estimation of parameters of under-damped second order plus dead time processes using relay feedback’, Comput. Chem. Eng., 2006, 30, (5), pp. 832837.
    22. 22)
      • 22. Shen, S.H., Wu, J.S., Yu, C.C.: ‘Use of biased-relay feedback for system identification’, AIChE J., 1996, 42, (4), pp. 11741180.
    23. 23)
      • 23. Shirazi, M., Zane, R., Maksimovic, D., et al: ‘Autotuning techniques for digitally controlled point-of-load converters with wide range of capacitive loads’. Proc. IEEE Applied Power Electronics Conf., California, USA, 2007, pp. 1420.
    24. 24)
      • 24. Stefanutti, W., Mattavelli, P., Saggini, S., et al: ‘Autotuning of digitally controlled DC–DC converters based on relay feedback’, IEEE Trans. Power Electron., 2007, 22, (1), pp. 199207.
    25. 25)
      • 25. Erickson, R.W., Maksimovic, D.: ‘Fundamentals of power electronics’ (Springer Science & Business Media, Springer, 2007, 2nd edn.).

Related content

This is a required field
Please enter a valid email address